To keep this blog up to date I would like to mention some changes done in code extensibility of D365 for Finance and Operations since my last post about D365FO extensibility, AX7 (D365) Chain of command with examples, in November 2017.

Replaceable keyword

In chain of command method extensions, now you are able to skip calling the base method (next call) by adding “Replaceable” attribute to the base method. This is added by Microsoft because of the high demand from the D365FO community for the ability to suppress the original method call when extending a method using chain of command. This attribute is available from on Platform Update 11.

[ExtensionOf(formcontrolstr(DemoForm, Button1))]final class DemoButton1_Extension{ public void clicked() { next clicked(); }}For more information, you can check the updated chain of command help from Microsoft :

From on Platform Update 17, you can change the form design pattern to “Custom” from a form extension, to be able to add your extended controls in a more flexible manner. This solves the problem that you get form pattern related errors when you try to add new extension controls on a form with a fixed, not changeable pattern :